摘要
为了探究σB因子对单增李斯特菌（LM）的生长影响,比较了LM-WaX12及其sigma B缺失突变株在不同pH值下生长动力学的差异。作者运用重叠延伸PCR（SOE-PCR）和同源重组的方法构建缺失SigB基因的LM突变株WaX12-△sigB;利用sigB外围引物扩增其两侧片段鉴定突变株,并且通过修正的Logistic模型拟合两个菌株在不同酸碱度下（p H 59）的生长曲线,分析各生长参数之间的差异性。结果表明,单增李斯特菌sigB缺失突变株构建成功;WaX12-△sigB和WaX12在p H 5的环境下最大比生长速率μmax、延滞期λ与最大菌浓MPD-OD均存在显著性差异（P〈0.05）,而在中性和碱性环境下二者无明显差异。
To explore the effect of σBin the growth of Listeria monocytogenes（LM）,we compared the growth kinetics of LM-WaX12 and its dull sig B mutant at different p H values. We used splicing by overlap extension PCR（SOE-PCR） and homologous recombination to construct the sigma B gene deleted mutant;The mutant was identified by the fragments that amplified by two sides primer of sig B. The growth curve of WaX12 and WaX12-sig B were fitted by modified Logistic model from p H5 to pH 9,as well as both growth kinetic parameters were analyzed. The results showed the △sig B mutant was constructed correctly. The maximum exponential growth rate（μmax）,lag phase duration（λ） and maximum population density（MPD-OD） of Wa X12-△sig B and WaX12 had all significant difference（p〈0.05） at p H 5,but had no different significant at neutral and alkali.
出处
《食品与生物技术学报》
CAS
CSCD
北大核心
2016年第5期477-484,共8页
Journal of Food Science and Biotechnology
基金
国家自然科学基金项目(31271870)
上海市科委计划项目(14DZ1205100
14320502100
12391901300)
上海市科技兴农重点攻关项目(沪农科攻字2014第3-5号)
关键词
单增李斯特菌
σB因子
酸性环境
生长动力学参数
Listeria monocytgenes
σB factor
acid stress stimulate
growth kinetic parameters
